TBX1 and cerebellar ataxia: As a result, heterozygous variants of the two candidate genes associated with DD/ID, GR, or facial dysmorphism were identified via duo exome sequencing in both the proband and her elder brother: FRMD4A (NM_018027.4: c.2296G>A/p.Ala766Thr) located on chr10:13,699,293 related to corpus callosum, agenesis, with facial anomalies, cerebellar ataxia (OMIM ID: #616819), and TBX1 (NM_080647.1: c.1480C>G/p.Pro494Ala) located on chr22:19,754,382 related to conotruncal anomaly face syndrome (OMIM ID: #217095).